THz Communications – A Candidate for a 6G Radio?

W the first 5G networks are about to be launched, the discussion within the scientific community about the next generation Beyond 5G or 6G has already kicked-off. One of the candidate technologies for a 6G radio access technology is THz communications, which uses spectrum mainly beyond 275 GHz enabling the use of channel bandwidths of several 10s of GHz. This contribution provides an overview on current state-of-the art of THz communications in research, standardization and regulation and discusses the challenges to make THz communications a promising candidate for a 6G radio

Transmisiones a 28GHz y 37GHz en interiores de trenes aplicando técnicas MISO-OFDM

[EN] This paper analyses a simulation of performance in an intra-wagon environment based on four scenarios. The 28 GHz and the 37 GHz bands are assessed for the use of 5G millimeter (mmWave) communications. The main objective was to analyses different multiple-input single-output orthogonal frequency division multiplexing (MISO-OFDM) techniques such as Hadamard quasiorthogonal space-time block code (HQSTBC) and transmit beamforming to analyze the throughput achieved as a function of the signal-to-noise ratio (SNR) applied. Starting from a measurement campaign, the performance is analyzed by scenario, applied band and in terms of the two algorithms used. In addition, the results are simulated with 4 and 8 transmitting antennas.Este trabajo ha sido financiado en parte por los proyectos PID2019-107885GB-C33 y TEC2017-86779-C2-2-R (AEI/FEDER, UE). Agradecer a Julia Iserte Villalba y Francisco M. Brox Lopez (personal de FGV) por facilitar la campaña de medidas.Sanchis Borrás, C.; Molina-García-Pardo, J.; Rubio Arjona, L.; Pascual García, J.; Rodrigo Peñarrocha, VM.; Llacer, LJ.; Reig, J. (2021). Transmisiones a 28GHz y 37GHz en interiores de trenes aplicando técnicas MISO-OFDM. Íñigo Cuiñas Gómez. 1-4. http://hdl.handle.net/10251/1910781

Resource Allocation for Device-to-Device Communications in Multi-Cell Multi-Band Heterogeneous Cellular Networks

Heterogeneous cellular networks (HCNs) with millimeter wave (mm-wave) communications are considered as a promising technology for the fifth generation mobile networks. Mm-wave has the potential to provide multiple gigabit data rate due to the broad spectrum. Unfortunately, additional free space path loss is also caused by the high carrier frequency. On the other hand, mm-wave signals are sensitive to obstacles and more vulnerable to blocking effects. To address this issue, highly directional narrow beams are utilized in mm-wave networks. Additionally, device-to-device (D2D) users make full use of their proximity and share uplink spectrum resources in HCNs to increase the spectrum efficiency and network capacity. Towards the caused complex interferences, the combination of D2D-enabled HCNs with small cells densely deployed and mm-wave communications poses a big challenge to the resource allocation problems. In this paper, we formulate the optimization problem of D2D communication spectrum resource allocation among multiple micro-wave bands and multiple mm-wave bands in HCNs. Then, considering the totally different propagation conditions on the two bands, a heuristic algorithm is proposed to maximize the system transmission rate and approximate the solutions with sufficient accuracies. Compared with other practical schemes, we carry out extensive simulations with different system parameters, and demonstrate the superior performance of the proposed scheme. In addition, the optimality and complexity are simulated to further verify effectiveness and efficiency.Comment: 13 pages, 11 figures, IEEE Transactions on Vehicular Technolog